Which services/tools do you self host specifically because it is something you use or have used at work?

Title says it for the most part. (this post assumes that you do some sort of IT work for a living, though I am sure there are non IT examples of this) What do you have running as a service, in production for personal use, that is something you use/used at a job in production? Like, do you use ansible to automate deployments because that is something you do at work? When you could still self host Atlasian stuff, did you have a Confluence instance because you had one at work? Or the other way around? Did self hosting Vault Warden give you the idea to do that for the company you work for? Grafana is also a good example that would work in both situations. Thanks in advanced and happy Monday everyone.